1. Field of the Invention
The present invention relates to an endoscope connector device, more specifically, the construction of a connector device for connecting a light guide for supplying illumination light to a light source unit and connecting an electric wire for obtaining video signals to a processor unit.
The invention relates to an endoscope cable lead-out unit, more specifically, a construction of a cable lead-out part which is used for a portion where an endoscope cable including various linear members is branched, and branches an electric wire from a light guide connector for connection to a light source unit.
2. Description of the Related Art
FIG. 7 and FIG. 8 show the construction of the related-art endoscope (electronic endoscope), and FIG. 7 is described in Japanese Examined Patent Application No. H07-24653, and FIG. 8 is described in Japanese Published Unexamined Patent Application NO. 2000-225093.
The endoscope apparatus of FIG. 7 includes an endoscope 51, a light source unit 52 and an image pickup control unit 53 placed on the light source unit 52, and a universal cable 54a of the endoscope 51 including a light guide and a signal line, etc., is connected to a front panel 52A (operation switch and the like are arranged thereon) of the light source unit 52 by a light source part connector 54b, and a signal cable 54c attached to the side face of this connector 54b is connected to the front panel 53A of the image pickup control unit 53 by a connector 54d. The signal cable 54c can be removed from the light source part connector 54b by a connector 54e. 
In the endoscope apparatus shown in FIG. 8, a light source unit 56 is placed on the processor unit 55, and to the front panel 56A (on which an operation switch, etc., are arranged) of the light source unit 56, an endoscope cable 57a including a light guide and an electric wire, etc., is connected by a connector part 57b, and a cable (electric cable) 57c attached to the lower side of the connector 57b is connected to the front panel 55A of the processor unit 55 by a connector 57a. Thus, in the related-art endoscope apparatus, a light guide and an electric wire (or a signal line) are installed inside one endoscope cable, and the light guide is connected to a light source unit 52 or 56 and the electric wire is connected to an image pickup control unit 53 or a processor unit 55.
In an endoscope (electronic endoscope) apparatus, a first cable including a light guide for supplying illumination light and an electric wire for obtaining video signals from an image pickup device is connected to a light source unit via a light guide connector, and a second cable of the endoscope which includes the electric wire extracted so as to be branched from the light guide connector is connected to a processor unit for video signal processing via an electric connector.
FIG. 18A and FIG. 18B show a construction example (employing a detachable connector type on the lead-out part of the electric wire) of the cable lead-out part of the light guide connector part, and in this light guide connector, a first cable (including a light guide and an electric wire 2) is laid from the endoscope distal end part, and a cylindrical lead-out part outer sheath 1b is integrally formed from a synthetic resin (hard) so as to project from the outer sheath 1a of the light guide connector main body. To the distal end side of this lead-out part outer sheath 1b, a metallic insert ring 1c is attached.
On the other hand, a pin supporting part 3a that connects the electric wire 2 guided from the light guide connector main body is installed inside a connector receiver 3b, and this connector receiver 3b is attached to the outer sheath 1b as shown in FIG. 18B by being fit to the inner surface of the insert ring 1c and fixed by screws 4 at a plurality of points. This connector receiver 3b is coupled to a connector inserting part to which the second cable is connected by a fixing ring 5, whereby the electric wire to the processor unit is linked.
However, the related-art endoscope connector devices have the following problems. Namely, in the endoscope apparatus of FIG. 7, as illustrated, the cable 54c to be attached to the light source part connector 54b is led out rightward along the front panel 52A, so that the cable 54c to be linked to the image pickup control unit 53 occupies the front of the front panels (operation panels) 52A and 53A of the light source unit 52 and the image pickup control unit 53, and remarkably disturbs various operations on the operation parts arranged on the front panels 52A and 53A. On the other hand, the cable 54c to be connected to the image pickup control unit 53 is made detachable by the connector 54e, however, when this is attached to or detached from the light source part connector 54b connected to the light source unit 52, the connector 54e is inserted or detached along (in parallel to) the front panel 52A at a position close to the front panel 52A of the light source unit 52, so that this detaching and attaching operation becomes difficult. In order to avoid this, it is also considered that the position of the connector 54e is separated far from the front panel 52A, however, this case lengthens the light source part connector 54b. 
Furthermore, in the endoscope apparatus of FIG. 8, obstruction of access to the operation part of the front panel as described above is rare, however, the upper and lower cables 57a and 57c attached to the connector part 57b are adjacent to each other, so that cleaning between these cables 57a and 57c becomes difficult. In addition, the distance between the base end portion (connector part 57b side) of the cable (electric wire cable) arranged on the lower side and the connecting position of the connector 57d in the processor unit 55 is short, the cable 57c is bent at a small curvature, and this burdens a great load on the cable 57c. 
Furthermore, in the case of FIG. 7, the cable 54c is arranged so as to be led out vertically to the right side from the light source part connector 54b, however, in the related art, in some cases, as shown in Japanese Published Unexamined Patent Application No. 2003-235797, opposite to the case of FIG. 7, the cable (corresponding to 54c) that extends to a signal processing unit is led out to the left side of the light guide connector (corresponding to 54b) also exists. In this case, disturbance of various operations on the front panels of the light source unit and the signal processing unit is reduced. However, in many endoscopes, it is required that the control portion (51A of FIG. 7) is held by the left hand and the light guide connector (light source part connector) is inserted into the light source unit by the right hand and then the cable and connector positioned on the left hand side are held and connected to the signal processing unit (processor unit), and this connection is troublesome. In addition, as described in FIG. 7, when the cable 54c is attachable to and detachable from the connector 54e, this connector 54e must be connected to the left side of the light source part connector 54b (light guide connector) by the right hand, and this connection is not easy.
In addition, in some the related-art cases, instead of attachment of the cables 54c and 57c toward the sides of the image pickup device control unit 53 and the processor unit 55 to the connectors 54b and 57b as shown in FIG. 7 and FIG. 8, an endoscope cable (54a or 57a) is branched into two of a light source side cable and a processor unit side cable at the middle of the cable as shown in Japanese Published Unexamined Patent Application No. H05-228104. However, in this case, the connectors of the two branched cables swing as pendulums, and the connectors themselves may be broken due to collision of these.
With the construction of the cable lead-out part of FIG. 18, since the insert ring 1c is arranged inside the outer sheath 1b made of a synthetic resin (plastic) and the connector receiver 3b is screw-tightened and fixed to this insert ring 1c, when the second cable is connected, a stress concentrates at the lead-out part outer sheath 1b around the insert ring 1c and may break the plastic-made outer sheath 1b. In addition, tightening and fixing of the plurality of screws (4) for connecting the connector receiver 3b are troublesome.
In order to avoid such breakage of the plastic-made lead-out part outer sheath 1b, it is considered that the lead-out part is reinforced by arranging a metallic supporter inside the lead-out part, however, in this case, it is necessary that the metallic supporter of the lead-out part is fixed to the metallic supporter or the like inside the light guide connector main body by some method, and this fixing method becomes complicated.